Turing Machines & Programmability
Basics of Turing Machines¶
Church's Thesis¶
Church’s Thesis states that: Every discrete function computable by any realisable machine is computable by a Turing Machine.
In other words, A turing machine can be made to replace any machine that already exists in general.
A function is computable if an algo can be made to do the job of the function.
The halting problem¶
The Universal Function¶
\(f_U (K,j) = T_K(j)\)
This means that a Turing Machine that runs \(U\) is a Turing machine that is capable of simulating an arbitrary Turing machine (with spec. \(K\)) on arbitrary input (\(j\)). This is called a Universal Turing Machine.